In conventional diodes, including that disclosed in Taiwanese Patent Application No. 76201274 entitled "Improved Diode Structure", the slugs are smaller than the die at the place near the contact area between the die and the slugs. The die thus extends beyond the slugs, at least near the contact area between the die and the slugs. Since the die is thus unprotected during the manufacturing process, such as assembling and curing, the die is easily damaged. The damage lowers the yield and reliability of the diodes.